Image sensor, electronic apparatus, and driving method of electronic apparatus

ABSTRACT

An image sensor that has a pixel array section in which pixels are arrayed in a two-dimensional manner in vertical and horizontal directions and that controls an exposure time of each pixel in a rolling shutter method is disclosed. The sensor includes control means for determining an electronic shutter occurrence number within one horizontal scanning period, which is the number of rows where electronic shutters are simultaneously performed in one horizontal scanning period, by an operation based on an address addition amount (P 1 , P 2 , P 3 , . . . , P N ) when a vertical address movement amount of the pixel array section for every one horizontal scanning period in an exposure regulation shutter, which is an electronic shutter for regulating exposure, executed corresponding to electric charge reading in each pixel is expressed as repetition of the address addition amount (P 1 , P 2 , P 3 , . . . , P N ).

CROSS REFERENCES TO RELATED APPLICATIONS

The present invention contains subject matter related to Japanese PatentApplication JP 2007-132099 filed in the Japanese Patent Office on May17, 2007, the entire contents of which being incorporated herein byreference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an image sensor, and more particularly,to an image sensor, an electronic apparatus, and a driving method of anelectronic apparatus capable of taking anti-blooming measures with asimple configuration.

2. Description of the Related Art

In the case of a digital camera, there are a global shutter method and arolling shutter method as main electronic shutter methods of an imagesensor. The global shutter method is a method of performing asimultaneous shutter operation on all pixels of a pixel array in whichpixels are arrayed in a two-dimensional manner, and the rolling shuttermethod is a method of shifting pixels, in which a shutter operation isperformed, in the unit of a row with time without performing thesimultaneous shutter operation on all pixels.

Furthermore, in the case of a digital camera, there is an operation modefor image adjustment called a preview mode in which adjustment of afocus or a viewing angle, adjustment of exposure, and the like areperformed before imaging a still image by performing reading on theentire pixel array of an image sensor.

In the preview mode, an image that the image sensor currently catches isdisplayed on a liquid crystal screen provided in a main body of adigital camera in order to make a user confirm the situation of theimage, for example. However, since the number of pixels on the liquidcrystal screen is smaller than the total pixel number of the imagesensor, it is necessary to perform pixel number compression conversionfor converting an image, which is obtained in all pixels of the imagesensor, into an image with a smaller number of pixels corresponding tothe number of pixels on the liquid crystal screen.

In this case, when a method of displaying an image on the liquid crystalscreen by reading all pixels of the image sensor and performing pixelnumber compression conversion by digital signal processing is adopted, acurrent consumed is increased due to an image compression conversionoperation, an operation of all pixels of the sensor, and the like. Forthis reason, a method of performing compression inside the image sensorby using a compression function of a compression circuit, which isprovided in the sensor, in the V direction (vertical direction) and theH direction (horizontal direction) is generally adopted.

For example, in a CMOS (complementary metal oxide semiconductor) imagesensor, a thinned-out image on which pixel number compression isexecuted is generated by performing pixel thinning out, in whichdiscontinuous rows (lines of pixels) are selected and interposed rowsare skipped, called V thinning out for the V direction.

Referring to FIG. 1, an operation of V thinning out in an image sensorusing a rolling shutter method will be described. FIG. 1 is an exampleof a ½ thinning-out mode in which ½ thinning out is performed in the Vdirection.

In FIG. 1, a horizontal axis indicates a time using one horizontalscanning period (1 [H]), which is a time for which one row located inthe horizontal direction of a pixel array section is scanned, as a unit,and a vertical axis indicates a row address that is an address of apixel row located in the V direction. Moreover, in FIG. 1, anaccumulation time (exposure time) of light (electric charges) is set to5 [H].

In addition, in the following description, pixels of R (red), G (green),and B (blue) of an image sensor are assumed to be arrayed in the Bayerarray.

Assuming that reading of electric charges is performed in (pixels of) arow corresponding to a row address n at predetermined time t [H], theaccumulation time is 5 [H]Accordingly, a shutter operation, that is, anoperation of sweeping out electric charges is performed at time (t−5)[H] that is 5 [H] earlier than time t [H]. In addition, in (pixels of) arow corresponding to the row address (n+1), a shutter operation isperformed at time (t−4) [H] corresponding to reading at time (t+1) [H].In addition, in the following description, performing a shutteroperation is simply referred to as performing a shutter or also referredto as occurrence of a shutter.

At time (t+2) [H], rows corresponding to row addresses (n+2) and (n+3)are skipped and a row corresponding to a row address (n+4) is read. Attime (t−3) [H], a shutter is performed in the row of the row address(n+4) corresponding to that described above. In addition, since a rowcorresponding to a row address (n+5) is read at time (t+3) [H], ashutter is performed in the row of the row address (n+5) correspondingto that described above at time (t−2) [H].

Following row addresses of read rows with a row of a row address n readat time t [H], a row read after the row of the row address n is a row ofa row address (n+1) when moving a row address by 1 and a row read afterthe row of the row address (n+1) is a row of a row address (n+4) whichhas moved from the row address (n+1) by 3.

Similarly, a row read after the row of the row address (n+4) is a row ofa row address (n+5) which has moved from the row address (n+4) by 1, anda row read after the row of the row address (n+5) is a row of a rowaddress (n+8) which has moved from the row address (n+5) by 3.

That is, the rows read in the V direction are rows obtained by making asequential movement with a movement amount of 1, 3, 1, 3, 1, 3, . . . .Accordingly, such V thinning-out operation is described as a Vthinning-out operation of address addition amount (1, 3).

By performing the V thinning-out operation of the address additionamount (1, 3), two read rows and two skipped rows are alternatelypresent in the V direction. The reason why two read rows and two skippedrows are alternately present in the V direction is because the imagesensor is arrayed in the Bayer array.

That is, in the Bayer array, a GB row where pixels of G and B arealternately arranged and a GR row where pixels of G and R arealternately arranged are alternately arrayed in the V direction.Accordingly, since it is necessary to read electric charges with the GBrow and the GR row adjacent to the GB row as a set, two read rows andtwo skipped rows are alternately provided.

In addition, it is sufficient not to continuously read GB rows or GRrows. That is, a GB row or a GR row adjacent to each other does notnecessarily need to be read continuously.

In the V thinning-out operation of the address addition amount (1, 3)described with reference to FIG. 1, a row that is not read even once inone frame period is present. Specifically, the row that is not read evenonce in one frame period is a row corresponding to a row address (n+2)or a row corresponding to a row address (n+3), for example. In the casewhen such row that is not read even once in one frame period is present,saturated electric charges overflow from the row that is not read andleak to a read row. That is, a phenomenon called blooming occurs, and asa result, the quality of an image may be deteriorated. Here, one frameperiod is a period for which an image of one frame is read and is equalto 1 [H]×(the number of rows in the V direction). In a setting (15 fps)for reading 15 frames in a second, one frame period is about 63 msec.

Therefore, a read operation in which anti-blooming measures are taken isalso performed in a known technique.

FIG. 2 is an example of a read operation in which anti-blooming measuresare taken in the ½ thinning-out operation of the address addition amount(1, 3) described with reference to FIG. 1.

As the anti-blooming measures, a shutter is also performed on a row thatis not read even once in one frame period. In the ½ thinning-outoperation of the address addition amount (1, 3), an exposure regulationshutter and an electronic shutter (hereinafter, suitably referred to asan anti-blooming shutter) executed as anti-blooming measures aresimultaneously performed on a pixel of a row address obtained byshifting a row address, in which an original electronic shutter(hereinafter, suitably referred to as an exposure regulation shutter)for regulating exposure is performed, by +2 rows as shown in FIG. 2. InFIG. 2, the exposure regulation shutter is indicated by the same doublecircle (⊙) as in FIG. 1, and the anti-blooming shutter is indicated by ablack circle (●).

Thus, it is possible to prevent blooming by executing the anti-bloomingshutter simultaneously with the exposure regulation shutter.

Next, an example of another V thinning-out operation mode in whichanti-blooming measures are taken in a ¼ thinning-out mode of addressaddition amount (3, 5) will be described with reference to FIG. 3.

Since the address addition amount is (3, 5), rows read in the Vdirection are pixels of rows obtained by moving a row address with amovement amount of 3, 5, 3, 5, 3, 5, . . . .

That is, assuming that reading of electric charges is performed in a rowcorresponding to a row address n at predetermined time t [H], anexposure regulation shutter is executed at time (t−5) [H] that is 5 [H]earlier than time t [H]. A row read at next time (t+1) [H] is a row of arow address (n+3) which has moved by 3 from the row address n readbefore, and the exposure regulation shutter is executed at a row of therow address (n+3) at time (t−4) [H] that is 5 [H] earlier than time(t+1) [H].

Then, a row read at next time (t+2) [H] is a row of a row address (n+8)which has moved by 5 from the row address (n+3) read before, and theexposure regulation shutter is executed at a row of the row address(n+8) at time (t−3) [H] that is 5 [H] earlier than time (t+2) [H].

Therefore, at time (t−5) [H], the anti-blooming shutter is executedsimultaneously with the exposure regulation shutter, which is executedin the row address n, at rows of the row addresses (n+1) and (n+2) whichare rows skipped among rows until a row of a row address (n+3) in whichthe exposure regulation shutter is executed at next time (t−4) [H].

Similarly, at time (t−4) [H], the anti-blooming shutter is executedsimultaneously with the exposure regulation shutter, which is executedin the row address (n+3), at rows of row addresses (n+4), (n+5), (n+6),and (n+7) which are rows skipped among rows until a row of a row address(n+8) in which the exposure regulation shutter is executed at next time(t−3) [H].

As described above, it is possible to take anti-blooming measures alsoin the ¼ thinning-out mode of the address addition amount (3, 5).

Moreover, the ¼ thinned-out image may also be generated in the case ofthe address addition amount (5, 3), (1, 7), or (7, 1) other than theaddress addition amount (3, 5) shown in FIG. 3.

Moreover, the ½ thinned-out image may also be generated in the case ofthe address addition amount (3, 1) other than the address additionamount (1, 3) shown in FIG. 2.

In addition, although not shown, in order to generate a ⅛ thinned-outimage, a combination of address addition amounts includes eight kinds of(1, 15), (3, 13), (5, 11), (7, 9), (9, 7), (11, 5), (13, 3), and (15,1).

Moreover, a ⅓ thinned-out image may be generated by a thinning-outoperation of an address addition amount (3) that repeats a value 3 as anaddress addition amount.

In recent years, a thinned-out image is often used as an image whenimaging a moving image as well as a preview mode. Accordingly, even inthe case of an image after V thinning out, a request of a high-qualityimage is increasing.

In addition, the size of a liquid crystal screen is diversified in adigital camera for mobile phones, for example. For this reason, types ofa V thinning-out operation mode tend to be diversified so that it ispossible to meet various kinds of liquid crystal screen sizes with oneimage sensor.

In a known technique, in order to meet various kinds of thinning-outmodes such that it is possible to meet various kinds of liquid crystalscreen sizes with one image sensor, the combination of address additionamounts and the position of an anti-blooming shutter at that time arestored in a table. Then, in the case of generating a predeterminedthinned-out image, required information is acquired from the tableaccording to the generated thinned-out image and a V thinning-outoperation is executed. Accordingly, since it is necessary to mount alarge-capacity table in a logic circuit in order to meet a number ofcombinations, it has been difficult to reduce the gate size and the chipsize.

Furthermore, in the case of performing short exposure under thesituation where a large amount of light is incident, blooming occursfrom a row adjacent to an object row of an exposure regulation shuttereven if the anti-blooming shutter described above is executed. As aresult, deterioration of the image quality has often occurred.

In addition, also in the case of performing all pixel reading, in whichthere is no skipped row and it is considered that the anti-bloomingshutter is not needed, the blooming occurs from the row adjacent to theobject row of the exposure regulation shutter. As a result,deterioration of the image quality has often occurred.

Referring to FIG. 4, occurrence of blooming from a row adjacent to anobject row of an exposure regulation shutter in a case of performing allpixel reading at accumulation time of 3 [H] will be described.

In an example shown in FIG. 4, the exposure regulation shutter of a rowaddress n read at time (t+3) [H] is executed at time t [H]. Adjacentrows of the row address n where the exposure regulation shutter isexecuted include two rows of row addresses (n−1) and (n+1). Since asweeping operation is performed on the row of the row address (n−1) atprevious time (t−1) [H], a photodiode is not saturated with electriccharges in many cases. Accordingly, a possibility that blooming willoccur is low.

On the other hand, in a photodiode corresponding to the row address(n+1), a sweeping operation previously performed is about one frameperiod before. Accordingly, since the photodiode is saturated withelectric charges in many cases, the electric charges over flow easily.For this reason, as shown by an arrow in FIG. 4, blooming from the rowaddress (n+1) to the row address n may occur immediately after theexposure regulation shutter of the row address n. Particularly in thecase when the row address (n+1) corresponds to a GR row of the Bayerarray and a component (red light) having a long wavelength is large inthe amount of incident light, leakage from an R pixel of the GR row to aG pixel of a GB row is large and deterioration of the image quality,such as a false color, caused by a difference between a G pixel of theGR row and the G pixel of the GB row and blooming occur.

As a known technique related to anti-blooming measures, there is atechnique of performing an electronic shutter (anti-blooming shutter) ina non-read region in order to avoid blooming from the non-read region(for example, refer to JP-A-2006-310932).

In addition, there is a method of alleviating blooming onto an adjacentpixel by continuously resetting floating diffusion in a power source andthrowing away electric charges leaking to the floating diffusion intothe power source or avoiding the blooming by adding a switch forresetting a photodiode of a pixel in a non-accumulation period (forexample, refer to JP-A-2004-11590).

SUMMARY OF THE INVENTION

However, in the technique proposed in JP-A-2006-310932, it is notpossible to avoid blooming from a read row to a read row that has beendescribed with reference to FIG. 4. Furthermore, the method disclosed inJP-A-2004-11590 has a problem that providing a switch for avoidingblooming is not suitable for miniaturization of a pixel.

Accordingly, since it is difficult to avoid a part of blooming or it isnecessary to mount a large-capacity table in a logic circuit or toprovide a switch in known anti-blooming techniques, it has beendifficult to reduce the gate size and the chip size.

Therefore, in view of the above, it is desirable to take anti-bloomingmeasures with a simple configuration.

According to a first embodiment of the present invention, there areprovided an image sensor and an electronic apparatus that have a pixelarray section in which pixels are arrayed in a two-dimensional manner invertical and horizontal directions and that control an exposure time ofeach pixel in a rolling shutter method including: control means fordetermining an electronic shutter occurrence number within onehorizontal scanning period, which is the number of rows where electronicshutters are simultaneously performed in one horizontal scanning period,by an operation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an exposureregulation shutter, which is an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)).

The control means may determine the electronic shutter occurrence numberwithin one horizontal scanning period such that the electronic shutteroccurrence number is equal in any one horizontal scanning period.

The control means may determine the electronic shutter occurrence numberwithin one horizontal scanning period such that the number of times ofelectronic shutters occurring in a period equivalent to one frame isequal in each row in the vertical direction.

The control means may determine the electronic shutter occurrence numberwithin one horizontal scanning period on the basis of a maximum value Qof an absolute value of each of the address addition amounts P₁, P₂, P₃,. . . , P_(N) in the case of generating a thinned-out image in which thenumber of pixels in the vertical or horizontal direction is thinned outaccording to the address addition amount (P₁, P₂, P₃, . . . , P_(N)).

The control means may make a control such that an electronic shutter isperformed on rows of addresses in the vertical direction that arecontinuous by the determined electronic shutter occurrence number withinone horizontal scanning period from an object row of the exposureregulation shutter.

The control means may make a control such that an electronic shutter isperformed on Q or more rows of addresses in the vertical direction thatare continuous from the object row of the exposure regulation shutter.

The control means may make a control such that the electronic shutter isperformed on (Q+2) rows of addresses in the vertical direction that arecontinuous from the object row of the exposure regulation shutter.

The control means may determine the electronic shutter occurrence numberwithin one horizontal scanning period on the basis of a maximum value Rof an absolute value of each of nearest-neighbor addition amounts P₁+P₂,P₂+P₃, P₃+P₄, . . . , P_(N−1)+P_(N), P_(N)+P₁, which are obtained byadding address addition amounts of rows adjacent to each other, in thecase of generating a thinned-out image in which the number of pixels inthe vertical or horizontal direction is thinned out according to theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)).

The control means may make a control such that an electronic shutter isperformed on discontinuous rows of addresses in the vertical directionwith every other row skipped from an object row of the exposureregulation shutter.

The control means may make a control such that the electronic shutter isperformed on (R/2) or more discontinuous rows of addresses in thevertical direction with every other row skipped from the object row ofthe exposure regulation shutter.

The control means may make a control such that the electronic shutter isperformed on ((R+2)/2)) discontinuous rows of addresses in the verticaldirection with every other row skipped from the object row of theexposure regulation shutter.

According to the first embodiment of the present invention, theelectronic shutter occurrence number within one horizontal scanningperiod, which is the number of rows where electronic shutters aresimultaneously performed within one horizontal scanning period, isdetermined by the operation based on the address addition amount (P₁,P₂, P₃, . . . , P_(N)).

According to a second embodiment of the present invention, there isprovided an image sensor including a pixel array section in which pixelsare arrayed in a two-dimensional manner in vertical and horizontaldirections. Reading of electric charges accumulated in pixels and anexposure regulation shutter, which is an operation of sweeping outunnecessary electric charges, are performed sequentially in the unit ofrows in the vertical direction, and a pre-shutter that is an operationof sweeping out unnecessary electric charges is performed before theexposure regulation shutter.

According to the second embodiment of the present invention, thepre-shutter that is an operation of sweeping out unnecessary electriccharges is performed before the exposure regulation shutter.

According to the first and second embodiments of the present invention,it is possible to take anti-blooming measures with a simpleconfiguration.

In addition, according to the first and second embodiments of thepresent invention, it is possible to reduce the gate size and the chipsize.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view explaining an operation in a ½ thinning-out mode;

FIG. 2 is a view illustrating an example in which anti-blooming measuresare taken in a ½ thinning-out operation;

FIG. 3 is a view illustrating an example in which anti-blooming measuresare taken in a ¼ thinning-out operation;

FIG. 4 is a view explaining occurrence of blooming at the time of allpixel reading;

FIG. 5 is a block diagram illustrating an example of the configurationof an image sensor according to an embodiment of the present invention;

FIG. 6 is a view illustrating a first embodiment of electronic shutteroccurrence number control;

FIG. 7 is a view illustrating a shutter control in a period of severalframes;

FIG. 8 is a view illustrating a second embodiment of the electronicshutter occurrence number control;

FIG. 9 is a view illustrating a third embodiment of the electronicshutter occurrence number control;

FIG. 10 is a view illustrating a fourth embodiment of the electronicshutter occurrence number control;

FIG. 11 is a view illustrating a fifth embodiment of the electronicshutter occurrence number control;

FIG. 12 is a block diagram illustrating an example of the configurationof an image sensor according to another embodiment of the presentinvention; and

FIG. 13 is a block diagram illustrating a camera according to anembodiment of the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the present invention will be described. Thecorrespondence relationship between configuration requirements of thepresent invention and embodiments described in this specification ordrawings is as follows. This description is made to confirm thatembodiments supporting the present invention are described in thisspecification or drawings. Therefore, even if there exists an embodimentthat is described in this specification or drawings but not describedherein as what corresponds to the configuration requirements of thepresent invention, the embodiment is not to be interpreted as anembodiment which does not correspond to the configuration requirements.In contrast, even if an embodiment is described herein as whatcorresponds to the configuration requirements, the embodiment is not tobe interpreted as an embodiment which does not correspond to aconfiguration requirement other than the configuration requirements.

An image sensor and an electronic apparatus according to a firstembodiment of the present invention have a pixel array section (forexample, a pixel array section 11 shown in FIG. 5) in which pixels arearrayed in a two-dimensional manner in vertical and horizontaldirections. The image sensor (for example, an image sensor 1 shown inFIG. 5) that controls an exposure time of each pixel in a rollingshutter method includes a control means (for example, a sensorcontroller 16 shown in FIG. 5) that determines an electronic shutteroccurrence number within one horizontal scanning period, which is thenumber of rows where electronic shutters are simultaneously performed inone horizontal scanning period, by an operation based on the addressaddition amount (P₁, P₂, P₃, . . . , P_(N)) when a vertical addressmovement amount of the pixel array section for every one horizontalscanning period in an electronic shutter for regulating exposure,executed corresponding to electric charge reading in each pixel isexpressed as repetition of the address addition amount (P₁, P₂, P₃, . .. , P_(N)).

Hereinafter, embodiments of the present invention will be described withreference to the accompanying drawings.

FIG. 5 is a block diagram illustrating an example of the configurationof an image sensor according to an embodiment of the present invention.

The image sensor 1 shown in FIG. 5 is an X-Y address access typesolid-state imaging device, for example, a CMOS image sensor.

The image sensor 1 is configured to include a pixel array section 11, aV selection circuit 12, analog front end circuits 13-1 to 13-M, ahorizontal selection circuit 14, an output amplifying circuit 15, and asensor controller 16.

In the pixel array section 11, photoelectric conversion elements (notshown) as pixels are arrayed in a two-dimensional manner in N rows in avertical direction by M columns in a horizontal direction (N rows×Mcolumns). Each pixel of the pixel array section 11 photoelectricallyconverts light incident thereon and outputs an imaging signal obtainedas the result. The V selection circuit 12 performs a charge readoperation and a charge sweeping operation of a pixel of the pixel arraysection 11 in the unit of a row on the basis of a control of the sensorcontroller 16. Rows on which the read operation and the sweepingoperation of the pixel array section 11 are performed are sequentiallyshifted with time. That is, the image sensor 1 is an image sensor usinga rolling shutter method. An imaging signal output from each pixel on arow selected by the V selection circuit 12 is supplied to the analogfront end circuits 13-1 to 13-M to which the position of the pixel inthe horizontal direction corresponds.

Each of the analog front end circuits 13-1 to 13-M performs CDS(correlated double sampling) processing and A/D (analog to digital)conversion processing on an imaging signal supplied from a pixel of thepixel array section 11.

In addition, an AD converter that converts an analog signal into adigital signal may be provided before the output amplifying circuit 15such that only CDS processing is performed in the analog front endcircuits 13-1 to 13-M.

The horizontal selection circuit 14 sequentially selects and outputsimaging signals of the analog front end circuits 13-1 to 13-M andsupplies the imaging signals to the output amplifying circuit 15. Theoutput amplifying circuit 15 amplifies and outputs the input imagingsignals.

The sensor controller 16 controls operation timing of the V selectioncircuit 12 and the horizontal selection circuit 14. In addition, thesensor controller 16 performs defect correction processing, AGCprocessing, and the like for correcting a defective pixel as needed.

In addition, the address addition amount when generating a thinned-outimage, for example, for matching with a liquid crystal screen having thenumber of pixels smaller than the number of all pixels of the pixelarray section 11 is supplied and designated from a DSP (digital signalprocessor) 51 that controls the image sensor 1, which will be describedin FIG. 12, to the sensor controller 16. The sensor controller 16controls the V selection circuit 12 such that the V selection circuit 12selects or does not select each row of the pixel array section 11 withthe designated address addition amount.

For example, as described above with reference to FIG. 1, when theaddress addition amount (1, 3) is supplied, the image sensor 1 generatesa ½ thinned-out image. In addition, also in the case where the addressaddition amount (3, 1) is supplied, the ½ thinned-out image isgenerated.

Similarly, the image sensor 1 generates a ¼ thinned-out image when oneof the address addition amounts (3, 5), (5, 3), (1, 7), and (7, 1) isdesignated from the DSP 51 and generates a ⅛ thinned-out image when oneof the address addition amounts (1, 15), (3, 13), (5, 11), (7, 9), (9,7), (11, 5), (13, 3), and (15, 1) is designated from the DSP 51.

In addition, in the case of generating a ⅓ thinned-out image or a ⅕thinned-out image, one of (3) or (5) is sufficient as a parameter of anaddress addition amount designated from the DSP 51.

In addition, also in the case of being designated as the addressaddition amount (3, 3), the ⅓ thinned-out image can be similarlygenerated. Also in the case of being designated as the address additionamount (3, 5, 3, 5), the ¼ thinned-out image can be generated.

That is, in general, it can be said that the address addition amount(P₁, P₂, P₃, . . . , P_(N)) (N≧1) is supplied from the DSP 51 to thesensor controller 16 in the case of generating a predeterminedthinned-out image. Moreover, all pixel reading in which thinning out isnot performed can also be expressed with the address addition amount(P₁, P₂, P₃, . . . , P_(N))=(1, 1, 1, . . . , 1).

Therefore, the sensor controller 16 controls the V selection circuit 12to select a predetermined row (row address) on which an exposureregulation shutter is executed, according to the address addition amount(P₁, P₂, P₃, . . . , P_(N)) designated from the DSP 51.

In addition, the sensor controller 16 also controls the V selectioncircuit 12 in connection with an anti-blooming shutter operation foravoiding blooming or a pre-shutter operation to be described later inaddition to the exposure regulation shutter. The sensor controller 16calculates the number of rows (hereinafter, suitably referred to as anelectronic shutter occurrence number), on which an electronic shutteroccurs within one horizontal scanning period (1 [H]), on the basis ofthe address addition amount (P₁, P₂, P₃, . . . , P_(N)) designated fromthe DSP 51 and controls the V selection circuit 12 according to thecalculation result.

Hereinafter, the way how the sensor controller 16 control the Vselection circuit 12 to perform an electronic shutter is described belowwith reference to FIGS. 6 to 11.

First Embodiment

FIG. 6 shows a first embodiment of a control of the electronic shutteroccurrence number made by the sensor controller 16.

FIG. 6 illustrates an example in which a pre-shutter, which is a shutterhaving a function of suppressing blooming onto a row (object row for theexposure regulation shutter) on which the exposure regulation shutter isexecuted, is executed on the V selection circuit 12 in addition to theexposure regulation shutter in the case when the address addition amount(1) is designated from the DSP 51, that is, in the case when the imagesensor 1 performs all pixel reading.

Similar to the case shown in FIG. 4, FIG. 6 illustrates an example inwhich the image sensor 1 performs all pixel reading with an accumulationtime 3 [H].

In FIG. 6, for example, an exposure regulation shutter of a row addressn read at time (t+3) [H] is executed at time t [H], but the V selectioncircuit 12 executes a pre-shutter on a row address (n+1) together withthe exposure regulation shutter of the row address n at time t [H]according to the control of the sensor controller 16.

Accordingly, for example, a sweeping operation is performed on a row ofa row address (n−1), which is a row below the row address n, at time(t−1) [H] before the time t [H]. Thus, since the row of the row address(n−1) is under exposure, blooming from the row of the row address (n−1)is suppressed. In addition, since unnecessary electric chargesaccumulated until that time are swept out on a row of a row address(n+1), which is a row above the row address n, by the pre-shutter,blooming from the row of the row address (n+1) is also suppressed.

As a result, blooming from the row address (n+1) to the row address n,which is shown by arrow in FIG. 4, can be prevented.

The pre-shutter control is performed by sequentially moving a rowaddress by +1 for every 1 [H] together with an exposure regulationshutter control.

In addition, paying attention to a row in connection with thepre-shutter control, it can be said that unnecessary electric chargesaccumulated until that time are swept out in each row by executing thepre-shutter before executing the exposure regulation shutter.

Furthermore, in the example shown in FIG. 6, timing at which thepre-shutter is performed is set to 1 [H] before performing the exposureregulation shutter. However, the timing at which the pre-shutter isperformed is not necessarily limited to 1 [H] before performing theexposure regulation shutter. For example, the timing at which thepre-shutter is performed may be 3 [H] before performing the exposureregulation shutter. That is, it is preferable to sweep out electriccharges beforehand so as not to leak while one prior row is beingexposed. However, it changes depending on a situation at which timeafter a pre-shutter electric charges leak. Accordingly, as shown in FIG.6, it is most preferable to perform the pre-shutter at the same timingas the exposure regulation shutter of one prior row.

In this case, it is general that an exposure time (accumulation time) inan image sensor changes according to the amount of light incident on apixel.

FIG. 7 is a view illustrating a shutter control in a periodcorresponding to several frames in a state where a horizontal axis inthe time direction shown in FIG. 6 is set to be long.

Solid lines 31 to 35 shown in FIG. 7 correspond to a read operationindicated by a circle (◯) in FIG. 6, and one-dotted chain lines 32′ to35′ correspond to a double circle (⊙) in FIG. 6 and are exposureregulation shutters corresponding to the read operation of the solidlines 31 to 35. In addition, a pre-shutter is not shown in FIG. 7. Inaddition, since one-time scanning in the entire V direction correspondsto an image of one frame, one solid line 32 or 33 shown in FIG. 7corresponds to an image of one frame.

As shown in FIG. 7, as a result that the exposure time (accumulationtime) has changed according to the amount of light incident on a pixel,an exposure time L32 of a image corresponding to the solid line 32, anexposure time L33 of a image corresponding to the solid line 33, anexposure time L34 of a image corresponding to the solid line 34, and anexposure time L35 of a image corresponding to the solid line 35 aredifferent from one another.

In FIG. 7, the electronic shutter occurrence number within onehorizontal scanning period, that is, the number of rows on which theelectronic shutter is operated in one horizontal scanning period (1 [H])is 3 (4 if a pre-shutter not shown in the drawing is included) in ahorizontal scanning period indicated by a dotted line and is 1 or 2 (2or 3 if a pre-shutter not shown in the drawing is included) in the otherhorizontal scanning periods.

Thus, since a load applied to a power source changes for everyhorizontal scanning period if the electronic shutter occurrence numberper 1 [H] changes, a horizontal line may be generated in the case when ahigh gain is applied.

Therefore, the sensor controller 16 controls the V selection circuit 12by inserting a dummy electronic shutter in a place, in which theelectronic shutter occurrence number is smaller than a maximumelectronic shutter occurrence number, in accordance with the maximumelectronic shutter occurrence number such that the electronic shutteroccurrence number is equal in any horizontal scanning period. Thus,since a load caused by an electronic shutter becomes uniform in eachhorizontal scanning period, it is possible to prevent the line describedabove from being generated. As a result, a high-quality image can begenerated.

In addition, paying attention to each row, the sensor controller 16 mayalso make a control such that the number of times of electronic shuttersoccurring in a period equivalent to one frame is equal in each row ofthe pixel array section 11. Although it may be considered thatincomplete transfer (transfer failure) easily occurs since a load causedby the pre-shutter or the dummy electronic shutter increases, it ispossible to make an influence of the incomplete transfer not noticeableas the image quality by making the number of times of electronicshutters occurring in a period equivalent to one frame equal in each rowof the pixel array section 11.

Second Embodiment

FIG. 8 shows a second embodiment of a control of the electronic shutteroccurrence number made by the sensor controller 16.

In the second embodiment, the sensor controller 16 determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value of an absolute value of each ofthe address addition amounts P₁, P₂, P₃, . . . , P_(N) when the addressaddition amount (P₁, P₂, P₃, . . . , P_(N)) is designated from the DSP51.

More specifically, assuming that the maximum value of the absolute valueof each of the address addition amounts P₁, P₂, P₃, . . . , P_(N) is Q,the sensor controller 16 sets the electronic shutter occurrence numberwithin one horizontal scanning period to Q or more and performs anelectronic shutter on rows of Q or more continuous row addresses with arow address of an object row for an exposure regulation shutter as areference.

The number of rows on which an anti-blooming shutter is operated in onehorizontal scanning period (hereinafter, suitably referred to as asimultaneous occurrence number of anti-blooming shutter) increases as athinning-out rate becomes higher, that is, the maximum value of theabsolute value of each of the address addition amounts P₁, P₂, P₃, . . ., P_(N) increases.

Here, an example of a case in which a row address movement of themaximum value Q is made when performing an exposure regulation shutterat time (t+1) [H] after an exposure regulation shutter is performed attime t [H], for example, is shown in FIG. 8.

Rows that require anti-blooming measures such that electric charges donot leak to pixels on a row of a row address n where an exposureregulation shutter is performed at time t [H] are rows of a row address(n+1) to a row address (n+Q−1) inserted between a row of a row address nand a row of a row address (n+Q), and the number of rows is (Q−1) rows.Accordingly, a minimum electronic shutter occurrence number that needsto be performed at timing of time t [H] is “Q” including the exposureregulation shutter of the row address n in addition to (Q−1) rows of arow address (n+1) to a row address (n+Q−1).

Therefore, deterioration of the image quality caused by blooming can besuppressed by setting the electronic shutter occurrence number withinone horizontal scanning period to Q or more.

Third Embodiment

FIG. 9 shows a third embodiment of a control of the electronic shutteroccurrence number made by the sensor controller 16.

In the third embodiment, the sensor controller 16 determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value of an absolute value of each ofthe nearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . ,P_(N−1)+P_(N), P_(N)+P₁, which are obtained by adding address additionamounts of rows adjacent to each other, when the address addition amount(P₁, P₂, P₃, . . . , P_(N)) is designated from the DSP 51.

More specifically, assuming that the maximum value of the absolute valueof each of the nearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, .. . , P_(N−1)+P_(N), P_(N)+P₁ is R, the sensor controller 16 sets theelectronic shutter occurrence number within one horizontal scanningperiod to R/2 or more and performs an electronic shutter on rows of R/2or more discontinuous row addresses with every other row skipped byusing a row address of a row, on which an exposure regulation shutter isto be executed, as a reference.

Similar to the second embodiment, the maximum value of the absolutevalue of each of the nearest-neighbor addition amounts P₁+P₂, P₂+P₃,P₃+P₄, . . . , P_(N−1)+P_(N), P_(N)+P₁ becomes higher as a thinning-outrate becomes higher, and the simultaneous occurrence number ofanti-blooming shutters within one horizontal scanning period increasesas the maximum value of the absolute value of each of thenearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . ,P_(N−1)+P_(N), P_(N)+P₁ becomes higher.

Here, for example, assuming that the address addition amount (P₁, P₂) isdesignated from the DSP 51, the nearest-neighbor addition amount isP₁+P₂ and the value (maximum value of the absolute value) is assumed tobe R.

An example of a case in which a row address movement from time t [H] totime (t+1) [H] occurs on a P₁ row and a row address movement from time(t+1) [H] to time (t+2) [H] occurs on a P₂ row is shown in FIG. 9.

The sensor controller 16 divides (R−1) rows, which are inserted betweenthe row address n of an object row for the exposure regulation shutterat time t [H] and the row addresses (n+R) of an object row for theexposure regulation shutter at time (t+2) [H], into two horizontalscanning periods of time t [H] and time (t+1) [H] and performs theanti-blooming shutter.

Therefore, the minimum electronic shutter occurrence number that needsto be performed within one horizontal scanning period is (R/2) when anobject row for the exposure regulation shutter is included, anddeterioration of the image quality caused by blooming can be suppressedby performing the electronic shutter on rows of (R/2) or morediscontinuous row addresses with every other row skipped including anexposure regulation shutter in each horizontal scanning period.

In addition, when (R/2) is a value that is not divisible, it ispreferable to throw away a fractional part.

Fourth Embodiment

FIG. 10 shows a fourth embodiment of a control of the electronic shutteroccurrence number made by the sensor controller 16.

The fourth embodiment is an embodiment in which a concept of thepre-shutter in the first embodiment is added to the second embodimentdescribed with reference to FIG. 8.

At time t [H], a pre-shutter needs to occur on a row of a row address(n+Q+1) corresponding to an adjacent row of a row address (n+Q) which isan object row of the exposure regulation shutter at time (t+1) [H].Accordingly, the electronic shutter occurrence number at time t [H]becomes (Q+2) obtained by adding two of pre-shutters to Q of theexposure regulation shutter and the anti-blooming shutter.

Therefore, deterioration of the image quality caused by blooming can besuppressed by setting the electronic shutter occurrence number withinone horizontal scanning period to (Q+2) or more.

In addition, although it is preferable that the electronic shutteroccurrence number within one horizontal scanning period be (Q+2) ormore, it is most preferable that the electronic shutter occurrencenumber within one horizontal scanning period be (Q+2) since a currentconsumed increases or transfer failure easily occurs as the electronicshutter occurrence number increases.

The fourth embodiment described above is an example of the thinning-outmode. However, the concept of the anti-blooming shutter and thepre-shutter may also be applied to all pixel reading. Since Q is 1 inthe case of all pixel reading, the electronic shutter occurrence numberwithin one horizontal scanning period is three.

Fifth Embodiment

FIG. 11 shows a fifth embodiment of a control of the electronic shutteroccurrence number made by the sensor controller 16.

The fifth embodiment is an embodiment in which a concept of thepre-shutter in the first embodiment is added to the third embodimentdescribed with reference to FIG. 9.

At time t [H] and time (t+1) [H], a pre-shutter needs to occur on a rowof a row address (n+R+1) corresponding to an adjacent row of a rowaddress (n+R) which is an object row of the exposure regulation shutterat time (t+2) [H]. In addition, since it is preferable to perform thepre-shutter in a state divided into two horizontal scanning periods oftime t [H] and time (t+1) [H], the minimum electronic shutter occurrencenumber that needs to be performed per one horizontal scanning period is((R+2)/2).

Therefore, deterioration of the image quality caused by blooming can besuppressed by setting the electronic shutter occurrence number withinone horizontal scanning period to ((R+2)/2) or more and performing anelectronic shutter on rows of discontinuous row addresses with everyother row skipped.

In addition, although it is preferable that the electronic shutteroccurrence number within one horizontal scanning period be ((R+2)/2) ormore, it is most preferable that the electronic shutter occurrencenumber within one horizontal scanning period be ((R+2)/2) since acurrent consumed increases or transfer failure easily occurs as theelectronic shutter occurrence number increases.

The fifth embodiment described above is an example of the thinning-outmode. However, the concept of the anti-blooming shutter and thepre-shutter may also be applied to all pixel reading. Since R is 2 inthe case of all pixel reading, the electronic shutter occurrence numberwithin one horizontal scanning period is two.

In the fourth and fifth embodiments described above, as can beunderstood with reference to FIGS. 10 and 11, it can be said that thepre-shutter can also function as an anti-blooming shutter since thepre-shutter is disposed to extend the anti-blooming shutter under thesame rule (continuous addresses or discontinuous addresses with everyother row skipped). Therefore, it can be said that the pre-shutter alsofunctions as an anti-blooming shutter.

Also in the second to fifth embodiments described above, as described inthe first embodiment with reference to FIG. 7, a high-quality image canbe generated by making equal the electronic shutter occurrence numberwithin one horizontal scanning period or the number of times ofelectronic shutters occurring in a period equivalent to one frame.

As described above, the image sensor 1 determines the electronic shutteroccurrence number within one horizontal scanning period, which includesthe exposure regulation shutter in addition to the pre-shutter or theanti-blooming shutter, by an operation based on the address additionamount (P₁, P₂, P₃, . . . , P_(N)) and makes a control according to thedetermined electronic shutter number. Thus, if the address additionamount (P₁, P₂, P₃, . . . , P_(N)) is designated, the electronic shutteroccurrence number within one horizontal scanning period can bedetermined by an operation. As a result, since it is not necessary toprepare a large-capacity table corresponding to various kinds ofthinned-out images, which has been performed in known techniques, it ispossible to reduce the chip size by reducing the gate size. That is, itis possible to take anti-blooming measures with a simple configuration.

Furthermore, in the above example, it has been described that theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)) is designated fromthe DSP 51 to the sensor controller 16 and the sensor controller 16calculates the electronic shutter occurrence number on the basis of thedesignated address addition amount (P₁, P₂, P₃, . . . , P_(N)). However,as shown in FIG. 12, the DSP 51 may perform an operation on theelectronic shutter occurrence number within one horizontal scanningperiod before supplying the address addition amount (P₁, P₂, P₃, . . . ,P_(N)) to the sensor controller 16 and may supply the electronic shutteroccurrence number within one horizontal scanning period to the sensorcontroller 16 together with the address addition amount (P₁, P₂, P₃, . .. , P_(N)) through register communication. The same effect can also beobtained in the configuration of an image sensor system including theimage sensor 1 and the DSP 51.

In the image sensor 1, since the electronic shutter occurrence numberwithin one horizontal scanning period is controlled (suppressed) by anoperation based on the address addition amount (P₁, P₂, P₃, . . . ,P_(N)), it is possible to reduce the occurrence number of unnecessaryelectronic shutters. As a result, transfer failure caused by an increasein power supply load is suppressed and the yield of the image sensor 1is improved. In addition, the power consumption is also realized.Moreover, a high-quality image can also be generated in a thinning-outmode by suppressing blooming on a read row required in the thinning-outmode.

In addition, by executing the pre-shutter, a high-quality image can begenerated, and in particular, color deviation occurring at the time ofshort exposure with a large amount of light is suppressed. Whether toperform the pre-shutter is determined only by an operation of adding 2to the maximum value Q of the absolute value of the address additionamount or the maximum value R of the absolute value of thenearest-neighbor addition amount when the pre-shutter is not performed,as described above. Accordingly, it is possible to easily control theelectronic shutter occurrence number including the pre-shutter.

In addition, the above-described control of the electronic shutteroccurrence number can also be applied to cases corresponding to allimage sizes, such as all pixel reading, ½ thinning out, ⅓ thinning out,¼ thinning out, ⅕ thinning out, and ⅛ thinning out. That is, the presentinvention is not limited to the pixel number of the specific imagesensor 1 and the size of an thinned-out image that is generated.

In addition, although only thinning out in the V direction has beendescribed in the above example, the same execution may be made inthinning out in the H direction.

Furthermore, in the present specification, a system refers to the entireapparatus configured to include a plurality of apparatuses.

FIG. 13 is a cross-sectional view illustrating a camera according toeach embodiment of the present invention. The camera according to thepresent embodiment is an example of a video camera capable ofphotographing a still image or a moving image.

The camera according to the present embodiment includes the image sensor1, an optical system 110, a shutter device 111, a driving circuit 51,and a signal processing circuit 112.

The optical system 110 makes image light (incident light) from a subjectbody imaged on an imaging surface of the image sensor 1. As a result,corresponding signal charges are accumulated within the image sensor 1for a predetermined period.

The shutter device 111 controls a light irradiation period and a lightblocking period with respect to the image sensor 1.

The driving circuit 51 supplies a driving signal for controlling atransfer operation of the image sensor 1 and a shutter operation of theshutter device 111. Signal transfer of the image sensor 1 is performedby the driving signal (timing signal) supplied from the driving circuit51. The signal processing circuit 112 performs various kinds of signalprocessing. A video signal subjected to signal processing is stored in astorage medium, such as a memory, or output to a monitor.

In the above embodiments, the case where the present invention isapplied to the image sensor 1, in which unit pixels that detect signalcharges corresponding to the light amount of visible light as a physicalamount are arrayed in a matrix, has been described as an example.However, the present invention is not limited to being applied to theimage sensor 1 but may also be applied to all kinds of column typesolid-state imaging devices in which a column circuit is disposed forevery pixel column of a pixel array section.

Furthermore, the present invention is not limited to being applied to asolid-state imaging device that detects the distribution of incidentlight amount of visible light and images the distribution as an imagebut may also be applied to a solid-state imaging device that imagesinfrared rays or X rays or the distribution of incident amount ofparticles and the like as an image or in a broader meaning, to all kindsof solid-state imaging devices (physical amount distribution detectingdevices), such as a fingerprint detecting sensor, which detect thedistribution of another physical amount, such as pressure orelectrostatic capacitance, and images the distribution as an image.

Furthermore, the present invention is not limited to being applied to asolid-state imaging device that sequentially scans unit pixels of apixel array section in the unit of a row and reads a pixel signal fromeach of the unit pixels but may also be applied to an X-Y address typesolid-state imaging device that selects an arbitrary pixel in the unitof a pixel and reads a signal from the selected pixel in the unit of apixel.

Furthermore, a solid-state imaging device may be formed in the form ofone chip or may be formed in the form of a module having an imagingfunction in a state where an imaging section and a signal processingsection or an optical system are packaged in groups.

In addition, the present invention is not limited to being applied tosolid-state imaging devices but may also be applied to imagingapparatuses. Here, the imaging apparatuses refer to a camera system,such as a digital camera or a video camera, or an electronic apparatushaving an imaging function, such as a mobile phone. In addition, theform of a module mounted in an electronic apparatus, that is, a cameramodule may be an imaging apparatus.

By using the image sensor 1 according to the above-described embodimentsas a solid-state imaging device in a video camera or a digital camera oran imaging apparatus, such as a camera module for a mobile apparatussuch as a mobile phone, it is possible to obtain a high-quality imagewith a simple configuration in the image sensor 1.

Embodiments of the present invention are not limited to theabove-described embodiments, but various modifications may be madewithout departing from the spirit and scope of the present invention.

1. An image sensor that has a pixel array section in which pixels arearrayed in a two-dimensional manner in vertical and horizontaldirections and that controls an exposure time of each pixel in a rollingshutter method, comprising: control means for determining an electronicshutter occurrence number within one horizontal scanning period, whichis the number of rows where electronic shutters are simultaneouslyperformed in one horizontal scanning period, by an operation based on anaddress addition amount (P₁, P₂, P₃, . . . , P_(N)) when a verticaladdress movement amount of the pixel array section for every onehorizontal scanning period in an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, the control means determines the electronicshutter occurrence number within one horizontal scanning period on thebasis of a maximum value Q of an absolute value of each of the addressaddition amounts P₁, P₂, P₃, . . . , P_(N) in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamount (P₁, P₂, P₃, . . . , P_(N)).
 2. The image sensor according toclaim 1, wherein the control means makes a control such that anelectronic shutter is performed on rows of addresses in the verticaldirection that are continuous by the determined electronic shutteroccurrence number within one horizontal scanning period from an objectrow of the exposure regulation shutter.
 3. The image sensor according toclaim 2, wherein the control means makes a control such that theelectronic shutter is performed on Q or more rows of addresses in thevertical direction that are continuous from the object row of theexposure regulation shutter.
 4. The image sensor according to claim 3,wherein the control means makes a control such that the electronicshutter is performed on (Q+2) rows of addresses in the verticaldirection that are continuous from the object row of the exposureregulation shutter.
 5. An image sensor that has a pixel array section inwhich pixels are arrayed in a two-dimensional manner in vertical andhorizontal directions and that controls an exposure time of each pixelin a rolling shutter method, comprising: control means for determiningan electronic shutter occurrence number within one horizontal scanningperiod, which is the number of rows where electronic shutters aresimultaneously performed in one horizontal scanning period, by anoperation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an electronicshutter for regulating exposure, executed corresponding to electriccharge reading in each pixel is expressed as repetition of the addressaddition amount (P₁, P₂, P₃, . . . , P_(N)), wherein, the control meansdetermines the electronic shutter occurrence number within onehorizontal scanning period on the basis of a maximum value R of anabsolute value of each of nearest-neighbor addition amounts P₁+P₂,P₂+P₃, P₃+P₄, . . . , P_(N-1)+P_(N), P_(N)+P₁, which are obtained byadding address addition amounts of rows adjacent to each other, in thecase of generating a thinned-out image in which the number of pixels inthe vertical or horizontal direction is thinned out according to theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)).
 6. The image sensoraccording to claim 5, wherein the control means makes a control suchthat an electronic shutter is performed on discontinuous rows ofaddresses in the vertical direction with every other row skipped from anobject row of the exposure regulation shutter.
 7. The image sensoraccording to claim 6, wherein the control means makes a control suchthat the electronic shutter is performed on (R/2) or more discontinuousrows of addresses in the vertical direction with every other row skippedfrom the object row of the exposure regulation shutter.
 8. The imagesensor according to claim 7, wherein the control means makes a controlsuch that the electronic shutter is performed on ((R+2)/2))discontinuous rows of addresses in the vertical direction with everyother row skipped from the object row of the exposure regulationshutter.
 9. An image sensor comprising: a pixel array section in whichpixels are arrayed in a two-dimensional manner in vertical andhorizontal directions; and a pre-shutter that is an operation ofsweeping out unnecessary electric charges is performed before anexposure regulation shutter; control means for determining an electronicshutter occurrence number within one horizontal scanning period, whichis the number of rows where electronic shutters are simultaneouslyperformed in one horizontal scanning period, by an operation based on anaddress addition amount (P₁, P₂, P₃, . . . , P_(N)) when a verticaladdress movement amount of the pixel array section for every onehorizontal scanning period in an electronic shutter for regulatingexposure, executed corresponding to the electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, reading of electric charges accumulated inpixels and the exposure regulation shutter, which is an operation ofsweeping out unnecessary electric charges, are performed sequentially inthe unit of rows in the vertical direction, and the control meansdetermines the electronic shutter occurrence number within onehorizontal scanning period on the basis of a maximum value Q of anabsolute value of each of the address addition amounts P₁, P₂, P₃, . . ., P_(N) in the case of generating a thinned-out image in which thenumber of pixels in the vertical or horizontal direction is thinned outaccording to the address addition amount (P₁, P₂, P₃, . . . , P_(N)).10. An electronic apparatus that has a pixel array section in whichpixels are arrayed in a two-dimensional manner in vertical andhorizontal directions and that controls an exposure time of each pixelin a rolling shutter method, comprising: control means for determiningan electronic shutter occurrence number within one horizontal scanningperiod, which is the number of rows where electronic shutters aresimultaneously performed in one horizontal scanning period, by anoperation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an exposureregulation shutter, which is an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, the control means determines the electronicshutter occurrence number within one horizontal scanning period on thebasis of a maximum value Q of an absolute value of each of the addressaddition amounts P₁, P₂, P₃, . . . , P_(N) in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamount (P₁, P₂, P₃, . . . , P_(N)).
 11. A driving method of anelectronic apparatus that has a pixel array section in which pixels arearrayed in a two-dimensional manner in vertical and horizontaldirections and that controls an exposure time of each pixel in a rollingshutter method, comprising the step of: determining an electronicshutter occurrence number within one horizontal scanning period, whichis the number of rows where electronic shutters are simultaneouslyperformed in one horizontal scanning period, by an operation based on anaddress addition amount (P₁, P₂, P₃, . . . , P_(N)) when a verticaladdress movement amount of the pixel array section for every onehorizontal scanning period in an exposure regulation shutter, which isan electronic shutter for regulating exposure, executed corresponding toelectric charge reading in each pixel is expressed as repetition of theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)), wherein, theelectronic shutter occurrence number is determined on the basis of amaximum value Q of an absolute value of each of the address additionamounts P₁, P₂, P₃, . . . , P_(N) in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamount (P₁, P₂, P₃, . . . , P_(N)).
 12. An image sensor that has a pixelarray section in which pixels are arrayed in a two-dimensional manner invertical and horizontal directions and that controls an exposure time ofeach pixel in a rolling shutter method, comprising: a control sectiondetermining an electronic shutter occurrence number within onehorizontal scanning period, which is the number of rows where electronicshutters are simultaneously performed in one horizontal scanning period,by an operation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an exposureregulation shutter, which is an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, the control sections determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value Q of an absolute value of each ofthe address addition amounts P₁, P₂, P₃, . . . , P_(N) in the case ofgenerating a thinned-out image in which the number of pixels in thevertical or horizontal direction is thinned out according to the addressaddition amount (P₁, P₂, P₃, . . . , P_(N)).
 13. An electronic apparatusthat has a pixel array section in which pixels are arrayed in atwo-dimensional manner in vertical and horizontal directions and thatcontrols an exposure time of each pixel in a rolling shutter method,comprising: a control section determining an electronic shutteroccurrence number within one horizontal scanning period, which is thenumber of rows where electronic shutters are simultaneously performed inone horizontal scanning period, by an operation based on an addressaddition amount (P₁, P₂, P₃, . . . , P_(N)) when a vertical addressmovement amount of the pixel array section for every one horizontalscanning period in an exposure regulation shutter, which is anelectronic shutter for regulating exposure, executed corresponding toelectric charge reading in each pixel is expressed as repetition of theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)), wherein, thecontrol means determines the electronic shutter occurrence number withinone horizontal scanning period on the basis of a maximum value Q of anabsolute value of each of the address addition amounts P₁, P₂, P₃, . . ., P_(N) in the case of generating a thinned-out image in which thenumber of pixels in the vertical or horizontal direction is thinned outaccording to the address addition amount (P₁, P₂, P₃, . . . , P_(N)).14. An image sensor comprising: a pixel array section in which pixelsare arrayed in a two-dimensional manner in vertical and horizontaldirection; and a pre-shutter that is an operation of sweeping outunnecessary electric charges is performed before an exposure regulationshutter; control means for determining an electronic shutter occurrencenumber within one horizontal scanning period, which is the number ofrows where electronic shutters are simultaneously performed in onehorizontal scanning period, by an operation based on an address additionamount (P₁, P₂, P₃, . . . , P_(N)) when a vertical address movementamount of the pixel array section for every one horizontal scanningperiod in an electronic shutter for regulating exposure, executedcorresponding to the electric charge reading in each pixel is expressedas repetition of the address addition amount (P₁, P₂, P₃, . . . ,P_(N)), wherein, reading of electric charges accumulated in pixels andthe exposure regulation shutter, which is an operation of sweeping outunnecessary electric charges, are performed sequentially in the unit ofrows in the vertical direction, and the control means determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value R of an absolute value of each ofthe nearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . ,P_(N-1)+P_(N), P_(N)+P₁, which are obtained by adding address additionamounts of rows adjacent to each other, in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamounts (P₁, P₂, P₃, . . . , P_(N)).
 15. An electronic apparatus thathas a pixel array section in which pixels are arrayed in atwo-dimensional manner in vertical and horizontal directions and thatcontrols an exposure time of each pixel in a rolling shutter method,comprising: control means for determining an electronic shutteroccurrence number within one horizontal scanning period, which is thenumber of rows where electronic shutters are simultaneously performed inone horizontal scanning period, by an operation based on an addressaddition amount (P₁, P₂, P₃, . . . , P_(N)) when a vertical addressmovement amount of the pixel array section for every one horizontalscanning period in an exposure regulation shutter, which is anelectronic shutter for regulating exposure, executed corresponding toelectric charge reading in each pixel is expressed as repetition of theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)), wherein, thecontrol means determines the electronic shutter occurrence number withinone horizontal scanning period on the basis of a maximum value R of anabsolute value of each of nearest-neighbor addition amounts P₁+P₂,P₂+P₃, P₃+P₄, . . . , P_(N-1)+P_(N), P_(N)+P₁, which are obtained byadding address addition amounts of rows adjacent to each other, in thecase of generating a thinned-out image in which the number of pixels inthe vertical or horizontal direction is thinned out according to theaddress addition amount (P₁, P₂, P₃, . . . , P_(N)).
 16. A drivingmethod of an electronic apparatus that has a pixel array section inwhich pixels are arrayed in a two-dimensional manner in vertical andhorizontal directions and that controls an exposure time of each pixelin a rolling shutter method, comprising the step of: determining anelectronic shutter occurrence number within one horizontal scanningperiod, which is the number of rows where electronic shutters aresimultaneously performed in one horizontal scanning period, by anoperation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an exposureregulation shutter, which is an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, the electronic shutter occurrence numberwithin one horizontal scanning period is determined on the basis of amaximum value R of an absolute value of each of nearest-neighboraddition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . , P_(N-1)+P_(N), P_(N)+P₁,which are obtained by adding address addition amounts of rows adjacentto each other, in the case of generating a thinned-out image in whichthe number of pixels in the vertical or horizontal direction is thinnedout according to the address addition amount (P₁, P₂, P₃, . . . ,P_(N)).
 17. An image sensor that has a pixel array section in whichpixels are arrayed in a two-dimensional manner in vertical andhorizontal directions and that controls an exposure time of each pixelin a rolling shutter method, comprising: a control section determiningan electronic shutter occurrence number within one horizontal scanningperiod, which is the number of rows where electronic shutters aresimultaneously performed in one horizontal scanning period, by anoperation based on an address addition amount (P₁, P₂, P₃, . . . ,P_(N)) when a vertical address movement amount of the pixel arraysection for every one horizontal scanning period in an exposureregulation shutter, which is an electronic shutter for regulatingexposure, executed corresponding to electric charge reading in eachpixel is expressed as repetition of the address addition amount (P₁, P₂,P₃, . . . , P_(N)), wherein, the control section determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value R of an absolute value of each ofnearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . ,P_(N-1)+P_(N), P_(N)+P₁, which are obtained by adding address additionamounts of rows adjacent to each other, in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamount (P₁, P₂, P₃, . . . , P_(N)).
 18. An electronic apparatus that hasa pixel array section in which pixels are arrayed in a two-dimensionalmanner in vertical and horizontal directions and that controls anexposure time of each pixel in a rolling shutter method, comprising: acontrol section determining an electronic shutter occurrence numberwithin one horizontal scanning period, which is the number of rows whereelectronic shutters are simultaneously performed in one horizontalscanning period, by an operation based on an address addition amount(P₁, P₂, P₃, . . . , P_(N)) when a vertical address movement amount ofthe pixel array section for every one horizontal scanning period in anexposure regulation shutter, which is an electronic shutter forregulating exposure, executed corresponding to electric charge readingin each pixel is expressed as repetition of the address addition amount(P₁, P₂, P₃, . . . , P_(N)), wherein, the control section determines theelectronic shutter occurrence number within one horizontal scanningperiod on the basis of a maximum value R of an absolute value of each ofnearest-neighbor addition amounts P₁+P₂, P₂+P₃, P₃+P₄, . . . ,P_(N-1)+P_(N), P_(N)+P₁, which are obtained by adding address additionamounts of rows adjacent to each other, in the case of generating athinned-out image in which the number of pixels in the vertical orhorizontal direction is thinned out according to the address additionamount (P₁, P₂, P₃, . . . , P_(N)).